The Bialy Eaters<br>By Mimi Sheraton<br>Broadway Books, 160 pp.<p>

If you can find the world in a grain of sand, you should certainly be able to find it in a four-inch diameter indented bread roll topped with onion and poppy seeds. That's what food journalist Mimi Sheraton sets out to do, using the Jewish delicacy known as the bialy as a window into the vanished world of Jewish Poland. Unable to find any bialys in their hometown of Bialystok, Sheraton journeys through the post-Holocaust diaspora of Bialystok Jews seeking to reconstruct their history and the urban Jewish culture they nourished.

Insisting that you cannot get a decent one outside of New York, and possibly one bakery in Israel, Sheraton is almost decadent in her connoisseurship of bialys. So are the aging remnants of Bialystok's pre-War Jewish community, now scattered everywhere from Argentina to Australia, who deplore what they see as a modern tendency toward undercooked bialys with stale onions and, shockingly, no poppy seeds. Their homespun reminiscences about the everyday rituals of making, buying and relishing this unprepossessing foodstuff are vivid and affecting. In a quiet way, they remind us of what was lost in the catastrophe.